1. Field of the Invention
This invention relates to a semiconductor device formed by joining a semiconductor chip with a tape carrier and also to a method of manufacturing this type of semiconductor device.
2. Description of the Prior Art
A type of semiconductor device including a semiconductor chip mounted on a tape carrier has received considerable notice in the field of manufacturing semiconductor devices since it enables improvements in automation and speedup of the manufacturing process as well as in the performance of initial tests of the semiconductor chip.
In general, this type of conventional semiconductor device has a structure such as that shown in FIGS. 20 and 21. That is, a semiconductor device 1 includes a semiconductor chip 2 and a tape carrier 3 on which the semiconductor device 2 is mounted. The tape carrier 3 is formed of a film 4 made of, e.g., a polyimide synthetic resin, and leads 5 disposed on the surface of the film 4.
The film 4 has perforations 6 regularly disposed along its opposite sides, and a rectangular opening 7 formed at its center, and outer lead holes 8 formed around the periphery of the opening 7. The central opening 7 is usually called a center device hole. The tips of the leads 5 extend over the opening 7 as inner leads 5a. Central portions of the leads 5 are positioned above the outer lead holes 8 as outer leads 5b. The rear ends of the leads 5 are formed as test pads 5c. The leads 5 are supported by a support portion 9 defined between the opening 7 and the outer lead holes 8. A semiconductor chip 2 is connected to the inner leads 5a of the leads 5 through bumps 10 (FIG. 21).
A conventional process of manufacturing this type of semiconductor device will be described below.
The semiconductor chip 2 is first introduced into the opening 7 of the film 4, and the inner leads 5a are connected to the bumps 10 formed on electrodes disposed on one surface 2u of the semiconductor chip 2. Ordinarily, this connection is effected by connecting the semiconductor chip 2 and the tape carrier 3 to each other thermocompression bonding. In this state, connection tests and operational tests of the semiconductor chip 2 are performed using the test pads 5c. Thereafter, the leads 5 are cut between the outer leads 5b and the test pads 5c, and bridging portions 11 formed between adjacent outer lead holes 8 are also cut. The outer leads 5b are then connected to a circuit board or the like, thereby enabling the semiconductor device to be used.
Thus, in the conventional semiconductor device, only the electrodes formed on one surface of the semiconductor chip 2 are connected to the leads 5 through the bumps 10. However, as semiconductor chips are developed in many variations, the need arises for a type of semiconductor chip, which includes electrodes on both the obverse and reverse sides. In this case, it is difficult to apply TAB (Tape Automated Bonding) technology, i.e. it is necessary to first connect electrodes on one side of the semiconductor chip 2 to the leads 5 and thereafter connect electrodes on the other surface of the chip 2 with desired leads 5 by wire bonding. As a result, this operation reduces the advantages of semiconductor device manufacturing using a tape carrier, i.e., automation and speedup of manufacture.